Device at musical instruments with a piano keyboard or the like

ABSTRACT

A musical instrument having a plurality of tone bars for the respective individual tones of the instrument. The tone bars are disposed in two parallel rows one overlying the other. A keyboard which may be of the type used in a piano is provided, and associated with each key is pass hammer which is adapted to be actuated by the associated key for striking the related tone bar. The hammers are positioned generally along one of the rows of tone bars, and in order that the hammers can strike the tone bars in the other row, at least some of the tone bars in the firstmentioned row define recesses therein along one edge so as to permit the hammer to passs therethrough and strike the associated tone bar in the other row. In addition, a resonance box is positioned over the tone bars and defines therein apertures which are disposed opposite the tone bars. Those apertures which are disposed opposite the tone bars in the more remote row of tone bars are larger than those which are disposed opposite the tone bars in the closer row of such tone bars.

United States Patent Jansson et al.

[54] IMPROVEMENTS IN DEVICE AT MUSICAL INSTRUMENTS WITH A PIANO KEYBOARD OR THE LIKE v [76] Inventors: Klas Einar Jansson, 60,-

Jarnvagsgatan, Motala; Staffan Gunnar Sjostrand, 3, Axgrand, Linkoping, both of Sweden 22 Filed: Feb. 27, 1913 211 App]. No.: 336,300

521 vs; Cl... 84/403, 84/404 [51] Int. Cl. G0ld 13/08 58 Field of Search 84/403, 404,449,478, 84/2, 3, 170, 171, 402

[56] References Cited UNITED sTATEs PATENTS 408,655 8/1889 Deagan et al 84/403 1,012,560 12/1911 Keller 84/404 1,524,418 l/l925 Bergst 84/170 2,512,777 6/1950 Rest et al...... 84/404 2,534,417 12/1950 Dargis 84/404 3,057,244 10/1962 Pearson, Jr. 84/404 3,443,469 5/1969 Hiraoka 84/403 FOREIGN PATENTS OR APPLICATIONS 203,802 9/1923 Great Britain 84/404 866,901 2/1953 Germany .1. 84/402 Dec. 31, 1974 Primary Examiner-Richard B. Wilkinson Assistant Examiner-Vit W. Miska Attorney, Agent, or FirmFred Philpitt [5 7] ABSTRACT A musical instrument having a plurality of tone bars for the respective individual tones of the instrument. The tone bars are disposed in two parallel rows one overlying the other. A keyboard which may be of the type used ina piano is provided, and associated with each key is pass hammer which is adapted to be actuated by the associated key for striking the related tone bar. The hammers are positioned generally along one of the rows of tone bars, and in orderthat the hammers can strike the tone bars in the other row, at least some of the tone bars in the first-mentioned row define recesses therein along one edge so as to permit the hammer to pass therethrough and strike the associated tone bar in the other row. In addition, a resonance box'is positioned over the tone bars and defines therein apertures which are disposed opposite the tone bars. Those apertures which are disposed opposite the tone bars in the more remote row of tone bars are larger than those which are disposed opposite the tone bars in the closer row of such tone bars.

v4 Claims, 7 Drawings Figures sum 10F 2 FIG.3I

FIGJ;

PATENTEI] BEDS 1 I974 IMPROVEMENT IN DEVICE AT MUSICAL INSTRUMENTS WITH A PIANO KEYBOARD OR THE LIKE The present invention relates to musical instruments with a piano keyboard or the, like, where the sounds are created by hammers actuating metal plates or the like sound sources have many advantages as compared with' classically built stringed instruments; especially as to tuning stability and uniformity of overtone series. Experiments made with tone bar instruments have shown that this stability of tuning is of very great importance not at least due to its effect of educating the ear in musical studies. I

In spite of these advantages, instruments of this kind have not been used to any considerable degree in combination with a keyboard of, for instance, piano type. This is due to the fact that tones of a low frequency necessitate tone bars that are wide and long in order to obtain a sufficient amplitude. The width of the bars require spreading of the touch mechanism in traditional piano mechanics, and this results in turn in an expensive and complicated construction with several technical problems that are difficult to solve as to the transfer of movements.

The present invention offers a simple solution of the problem of using tone bars in connection with a piano keyboard and is substantially characterized in that the tone bars are adapted in two rows over each other with one tone in one row and the following tone (or more correctly the following tone bar) in the other row etc. and that each tone bar is actuated by the corresponding hammer and key, the tone bars in one row being provided with recesses at the edges to let through the hammers actuating the tone bars of the other row and that a resonance-box is adapted over the tone bars and provided with resonance holes (sound slits) at the side of the box directed to the rows of bars, which holes at least for the lower tones are wider over the bars located further away and narrower over those located closest to the box.

One embodiment of the invention, which as to its technical design can vary considerably within the scope of the inventive idea will be described below with reference to the enclosed drawings, where:

FIG. 1 shows a tone bar according to the invention;

FIG. 2 shows schematically how the tonebars are adapted in two rows, in this case under a resonancebox;

FIG. 3 shows a view of two adjacent tone bars, in this case as seen from below;

FIG. 4 shows an end view of the two rows of tone bars with the resonance-box over the tone bars and part'of the touch mechanism in this case adapted under the same;

FIG. 5A shows a part view from below of the resonance-box with resonance holes made therein with the resonance-box opened to show how the resonance holes are designed relative to the lower tone bars,

FIG. 5B shows how the tone bars are arranged opposite the resonance holes in the resonance box; and

FIG. 6 shows finally. a schematical view of a resonance-box as seen from below.

In the drawings, 11 indicates schematically the profile of a tone bar with recesses 2 at the edges in order to make room forahammer (6 in FIG. 4). In the tone bar two holes 3 are made intended for preferably pins covered with rubber, which secure the tone barto a tone board. In FIG. 2 a resonance-box 4 is schematically indicated, in this case adapted over two rows of tone bars. The tone bars of the upper row are designated by 1a and lb, and those of the lower row by 2a and 2b. The tone bars rest in this embodiment on rubber cords (or so-called valve rubber) 10, which makes possible the oscillations of the bars around their nodes, which preferably coincide with the position of the holes 3 in the longitudinal direction of the bars.

Every other bar is situated in the upper row and every other in the lower one. In this way, a lateral contraction of the key bars is obtained, which makes possible the same division between the tone bars as between the keys of the keyboard, and, moreover, the sound from the key bars 2a, 2b etc., of the lower row reaches the resonance-box 4 between the tone bars of the upper 2 row. As a consequence of the fact that the bars of the lower row are placed further away, the resonance-box must at least for the lower tones be shaped in view of this in order that the tone bars of the lower row will not provide less acoustic effect than those of the upper row. This. problem has been solved according to the invention in the way indicated in FIG. 5 and FIG. 6 by making holes in the bottom of the resonance-box. For

lower tones these holes are preferably T-shaped, the

sound slit c-a' collecting more effectively the sound waves from the bar 2a. A small or narrow part of the sound slit corresponds to the bars l a and 11 b; it is important that the distance c-d is adapted to the length of the bar and to the aperture between the bars la and 1b in order that the amplification should be uniform for the adjacent bars of the musical scale. Tests have been made showing that it is possible to eliminate in this way the disadvantage ofthe bars having different distances to the resonance-box.

FIG. 6 shows schematically how the sound slits in a resonance-box can be embodied; at higher tones the resonance slit can be continuous or designed rectangularly, as these are not so sensitive to the difference of the distance to the resonance-box as the bass tones. Moreover, in this Figure there is indicated by means of dotted lines that the resonance-box is divided into partitions as well as that the resonance volume (the depth) of the box is bigger above the bass tones than over the treble tones.

The device described above consistingof tone bars and resonance-box can in principle be brought to sound by any suitable touching device. In FIG. 4 a simple construction is shown schematically, where the bars I are struck by means of a hammer 6. Each hammer 6 is mounted on a spring 7, which in its turnis mounted on a key 6. The recesses 2 in the lower row make in this way the passage of the hammer 6 possible. The Figure I being necessary to use double mechanics and double resonance-boxes. Such a construction creates such great problems with touch resistance and extensions of mechanics thereby accounting for the absence of earlier tests so far as is known with traditional piano mechanics. I

An instrument according to the invention will be considerably cheaper than a piano and need never be tuned, and therefore it replaces with advantage the piano to a considerable extent, not at least for educational purposes.

The design itself can be considerably varied without deviating from the inventive idea. Thus the resonancebox can, for instance, be adapted to hang under the rows of tone bars, and the touch mechanism preferably over the same. The separate details can also be varied, for instance the design of the resonance box, which can be made more or less costly depending on which degree of perfection is aimed at.

What we claim is: v

l. A musical instrument comprising in combination:

a plurality of tone bars for the respective individual tones of the instrument, said tone bars being disposed in two parallel rows one overlying the other,

tone bar striking means comprising a plurality of keys and a hammer for each key adapted to be actuated by the associated key for striking the related tone bar,

said hammers being positioned generally along one of said rows of tone bars, at least some of the tone bars in said one row defining a recess for permitting a hammer to pass therethrough and strike an associated tone bar in the other said row,

and a resonance box positioned over said tone bars and defining therein apertures in the side of the resonance box disposed opposite said tone bars, at least some of said apertures which are disposed opposite those tone bars in the row more remote from said resonance box being larger than those apertures which are'disposed opposite tone bars in the row closer to said resonance box.

2. The instrument of claim 1 wherein said resonance box over its length as measured in the direction of said rows of tone bars is divided internally by partitions.

3. The instrument of claim 1 wherein each said tone bar defining a recess therein has its length varied from that normally provided in accordance with the predetermined tone to be produced to compensate for the effect of said recess.

4. A musical instrument comprising in combination:

a plurality of tone bars for the respective individual tones of the instrument, said tone'bars being disposed in two parallel rows' overlying each other,

tone bar striking means comprising a plurality of keys and a hammer for each key adapted to be actuated by the associated key for striking the related tone bar,

said hammers being positioned generally along one of said rows of tone bars, at least some of the tone bars in said one row including recesses which provide an open space between adjacent tone bars in said one row, thereby permitting a hammer to pass through the open space so provided and to strike an associated tone bar in the other said row, and

a resonance box positioned adjacent said tone bars and defining therein apertures in the side ofthe resonance box disposed opposite said tone bars. 

1. A musical instrument comprising in combination: a plurality of tone bars for the respective individual tones of the instrument, said tone bars being disposed in two parallel rows one overlying the other, tone bar striking means comprising a plurality of keys and a hammer for each key adapted to be actuated by the associated key for striking the related tone bar, said hammers being positioned generally along one of said rows of tone bars, at least some of the tone bars in said one row defining a recess for permitting a hammer to pass therethrough and strike an associated tone bar in the other said row, and a resonance box positioned over said tone bars and defining therein apertures in the side of the resonance box disposed opposite said tone bars, at least some of said apertures which are disposed opposite those tone bars in the row more remote from said resonance box being larger than those apertures which are disposed opposite tone bars in the row closer to said resonance box.
 2. The instrument of claim 1 wherein said resonance box over its length as measured in the direction of said rows of tone bars is divided internally by partitions.
 3. The instrument of claim 1 wherein each said tone bar defining a recess therein has its length varied from that normally provided in accordance with the predetermined tone to be produced to compensate for the effect of said recess.
 4. A musical instrument comprising in combination: a plurality of tone bars for the respective individual tones of the instrument, said tone bars being disposed in two parallel rows overlying each other, tone bar striking means comprising a plurality of keys and a hammer for each key adapted to be actuated by the associated key for striking the related tone bar, said hammers being positioned generally along one of said rows of tone bars, at least some of the tone bars in said one row including recesses which provide an open space between adjacent tone bars in said one row, thereby permitting a hammer to pass through the open space so provided and to strike an associated tone bar in the other said row, and a resonance box positioned adjacent said tone bars and defining therein apertures in the side of the resonance box disposed opposite said tone bars. 